Spaceweather.com
"Comet Pojmanski (C/2006 A1) has a bright green head," says Chris Schur who took this picture yesterday at dawn from Payson, Arizona.
What makes a comet green? The atmosphere of the comet--called "the coma"--contains cyanogen (CN), a poisonous gas, and diatomic carbon (C2). Both of these substances glow green when illuminated by sunlight.
See for yourself. Comet Pojmanski (5th magnitude) is an easy target for backyard telescopes. Look for it left of Venus in the early morning sky: MAP
New asteroid at top of Earth-threat list
Kimm Groshong
NewScientist.com news service
01 March 2006
Observations by astronomers tracking near-Earth asteroids have raised a new object to the top of the Earth-threat list.
The asteroid could strike the Earth in 2102. However, Don Yeomans, manager of NASA's Near Earth Object Program at the Jet Propulsion Laboratory in Pasadena, California, US, told New Scientist: "The most likely situation, by far, is that additional observations will bring it back down to a zero."
He adds: "We're more likely to be hit between now and then by an object that we don't know about."
On 23 February, new observations allowed researchers to more accurately calculate the orbit of the asteroid, named 2004 VD17, which was originally detected by the Massachusetts Institute of Technology's LINEAR project. Since the improvement did not rule out a potential collision with the Earth on 4 May 2102, they increased the asteroid's rating to level 2 on the Torino Scale, a relatively rare event.
Degrees of danger
The Torino Scale, adopted in 1999, is akin to a Richter scale for asteroid impacts. The vast majority of the 4000 or so near-Earth objects (NEOs) detected so far have been assigned to level zero on the Torino scale, meaning they have "no likely consequences".
Level 1, colour-coded green, suggests a possible impact that "merits careful monitoring". Beyond that, the risk continues to rise along the scale ? levels 2, 3 and 4 are yellow; 5, 6 and 7 are orange; while 8, 9 and 10 earn red.
The highest level ever reached by an asteroid was level 4 by Apophis (2004 MN4) in December 2004, but subsequent calculations downgraded that concern to a level 1. So VD17 currently claims the top spot on NASA's online list of potential asteroid impacts.
Despite the rarity of the yellow designation, Yeomans says "Torino 2 is not very alarming." He notes that the scale does not take account of how soon an impact may occur, unlike its rival, the Palermo Scale.
Based on current observations, he says the asteroid has a 1 in 1600 chance of striking the Earth in 2102 and a 1 in 500,000 chance of hitting two years later. But further observations will soon refine the orbit calculation for VD17 ? and hopefully ease minds.
NEO hunter, Andrea Milani Comparetti of the University of Pisa, Italy, says VD17 "is a serious problem, but not for our generation". He also notes that VD17 is dim and distant and is not projected to pass close by the Earth before 2102. "You will need fairly powerful telescopes to see it before it arrives," he told New Scientist.
Smaller threats
Since 1998, NASA has had a US Congressional mandate to locate 90% of all NEOs of 1 kilometre or larger by 2008. Yeomans says that 830 out of a predicted 1100 have been found so far, along with thousands of smaller objects.
In the NASA Authorization Act of 2005, Congress directed the space agency to study and report back on the best way to cost-effectively locate 90% of all asteroids down to a diameter of just 140 metres. Yeomans says there are likely to be about 100,000 such NEOs.
Yeomans and Bill Bottke of the Southwest Research Institute in Boulder, Colorado, were both members of a team that reported in 2003 that a survey to locate such small asteroids would be cost-effective, considering the damage an impact could cause. Bottke says the group found that to find 90% of the remaining hazard would cost roughly $300 million.
2004 VD17 is estimated to have a diameter of about 580 metres. An asteroid of that size would produce an impact crater about 10 kilometres wide and an earthquake of magnitude 7.4 if it struck land.
href="http://www.newscientistspace.com/article/mg18925411.100-when-aliens-rained-over-india.html" target="_blank">When aliens rained over
India
Hazel Muir
New Scientist Print Edition
02 March 2006
I'VE heard plenty of tales about freak weather that are strange, but nonetheless true. In August 2000, a shower of sprats, dead but conveniently still fresh, fell from the skies onto the English port of Great Yarmouth just after a thunderstorm. A torrent of live toads pelted a Mexican town in June 1997. And in 2001, 50 tonnes of alien life forms rained down from the clouds over India.
Actually, I'm not sure that the alien story is true. But it is surprisingly persistent. I first saw it in 2003 in a scientific paper written by Godfrey Louis, a physicist working in the Indian state of Kerala, on the country's southern tip. He described how, during two months in 2001, red rain fell sporadically right across the state. No one could explain it, but after lengthy studies of red particles in the rainwater, Louis came to the extraordinary conclusion that they were alien microbes that hitched a ride to Earth on a comet.
To most people, that would sound eccentric at the very least. It looked as if the idea would quietly wither on the vine. Then in January this year, it turned out that Louis's theory is still alive and kicking, and soon to roll off the press in a reputable peer-reviewed journal. I sent a preprint to several researchers, who despite voicing mixed opinions almost all agreed about one thing: the red particles Louis describes look biological.
"If they're not living cells, I don't know what they are," said Milton Wainwright, a microbiologist at the University of Sheffield, UK. "Maybe this is the beginning of something amazing." Another scientist simply commented: "Sounds like bullshit to me." That was it - I could resist this weird and controversial story no longer.
The saga dates back to 25 July 2001, when red rain fell in a district of Kerala called Kottayam. Over the following two months, red rain fell sporadically there and in other Kerala districts, gradually tailing off over time. The local newspapers buzzed with eyewitness reports. People found their clothes stained by red raindrops. Although these usually had a mild red tint, sometimes the colour was so strong that witnesses compared it to blood. Usually, the red rain would fall for less than 20 minutes.
Louis, a solid-state physicist at Mahatma Gandhi University in Kottayam, was intrigued and decided to study the rain with his student Santhosh Kumar. The pair compiled more than 120 reports of the rain from local newspapers and other sources, and gathered samples of the red rain from spots more than 100 kilometres apart (see Map).
Under the microscope, they could see red particles 4 to 10 micrometres wide with an average density of about 9 million particles per millilitre. When they dried the samples they found that each cubic metre of rainwater contained about 100 grams of the red stuff. Louis suggests 5 millimetres of red rain would typically have fallen over a square-kilometre area during each of about 100 downpours. That would make 500,000 cubic metres of water in total, containing a staggering 50 tonnes of red particles.
What could they be? One possibility was that fine red sand had blown over Kerala from some distant desert. Sand can travel amazingly far. In July 1968, for instance, fine grit in raindrops left parts of southern England coloured rusty red. The sand had blown from the Sahara inside a massive high-pressure system before falling in a rain shower.
But under the microscope, the red particles that rained on Kerala were clearly not sand. Electron micrographs show that they are shaped like biological cells. "They don't look anything like sand, they look biological," says Monica Grady, a meteorite expert at the UK's Open University in Milton Keynes. The cells, if that's what they are, are mostly cup-shaped and have a thick wall.
One type of analysis shows their chemical make-up is about 50 per cent carbon and 45 per cent oxygen by weight, along with traces of other elements such as sodium and iron. That's consistent with the components of a biological cell, according to Jeffrey Walker, a molecular biologist from the University of Colorado in Boulder. But although many of the cells have some kind of detached inner capsule, there is no visible cell nucleus, and tests for DNA that Louis carried out came back negative.
Louis rules out a distant terrestrial source for the mysterious particles, because the red rain was concentrated over Kerala for two months despite changes in climate and wind patterns. Could the cells instead be local pollen or fungal spores washed off trees and houses by the rain? Louis says no, because red rain was collected in buckets placed in wide-open spaces. Equally, he says, the red particles can't be pollen or spores from the ground that accumulated in the atmosphere, because the rain would then have been red at the start of a shower; often the colour came later.
Instead, he links the coloured rain to a meteor airburst. During the early hours of 25 July 2001, just hours before the first red rain fell, several people in the Kottayam district heard a loud sonic boom that made their houses rattle. Louis has interviewed some of those who heard it, and concluded that it was too loud to have been an ordinary thunderclap. It's possible that an incoming meteor exploded in the atmosphere.
Louis then takes a large leap and suggests the meteor was a fragment of a comet harbouring microbes from space. He thinks that is the only explanation for the red rain pattern. The meteor flew over Kerala from north to south, he suggests, shedding fragments and alien microbes in the upper atmosphere, before finally exploding over Kottayam district. There, some of the red microbes mixed with rain clouds and fell fairly quickly, while the rest gradually settled into the clouds and fell in rain over the following weeks.
"Yes, it is an extraordinary claim, but I have to report what I observe," says Louis. "We are not able to explain it by assuming a terrestrial object." The red particles look like biological cells, he stresses, but contain no DNA. They could therefore be exotic, alien life forms unknown to science.
Far-fetched? Certainly sounds it. But the idea would undoubtedly have appealed to the late University of Cambridge astronomer Fred Hoyle, champion of the "panspermia" theory. With Chandra Wickramasinghe of Cardiff University, UK, Hoyle developed the idea that life on Earth evolved from microbes that fell to its surface on a comet. In this picture, primitive life forms could be ubiquitous throughout the universe, peppered among the planets and the stars.
Philosophically, panspermia has a certain appeal. It could resolve the genuine puzzle about why life arose on Earth so fast. The solar system began its life some 4.5 billion years ago as a hostile interplanetary war zone, with rocky missiles pelting everything in sight. Around 3.9 billion years ago, the Earth suffered a particularly violent bombardment that pulverised its crust. Yet carbon isotopes in ancient rocks hint that primitive microbes were thriving just 50,000 years later - a blink of an eye in evolutionary terms. Panspermia allows off-the-shelf microbes to arrive on the newly hospitable Earth. This waves away the apparent paradox that the Earth is the only place in the entire cosmos where we've found signs of life. From experience, astronomers assume that if something has occurred once in the universe, it's probably occurred many more times - we just haven't seen it yet.
Panspermia developed a touch of giggle-factor when Hoyle and Wickramasinghe blamed extraterrestrial viruses for flu epidemics. But it has come back into fashion of late, and proponents argue there's plenty of evidence for it. Experiments have shown that some tough bacteria can survive for years in space, despite the extreme cold and high levels of radiation. Others have proved that some of these bugs could survive the high-speed collisions that they would experience if they slammed into the Earth on a comet.
The idea of primitive microbes flying around the solar system in its early days is not as wild as it seems. "Most of the rocks near the surface of the Earth are shot through with microbial life. It would be a fairly simple thing for a little piece of the crust to be ejected and life survive and land somewhere else," says Walker. On balance, he says, he'd bet that life began here on Earth. But he wouldn't be that surprised if evidence emerged that life started somewhere else and was delivered to Earth by a hunk of space rock.
Extraordinary claims
In 1996, Martian meteorite ALH 84001 caused a furore when some scientists claimed that it harboured fossil bugs. The case was never proved. "But the most interesting information that we gathered from that meteorite was that when the rock was ejected from Mars and travelled to the Earth, the temperature of the interior never exceeded something like 50 ?C," says Walker. "Plenty of microbes can survive that, especially spores."
All in all, it seems that panspermia could work. Now Louis thinks the red rain of Kerala provides evidence that it actually does. His new report on the subject, which will appear in Astrophysics and Space Science in the next few months, is impressive in its detail, according to Wainwright. "Everything in the paper is done correctly, there's nothing wacky about it," he says. Grady says it is "very, very thorough indeed".
However, if scientists have a favourite quote, it's this one, popularised by Carl Sagan: "extraordinary claims require extraordinary evidence". I'm hearing it a lot in discussions about the red rain of Kerala. Grady thinks Louis and Kumar have jumped to the extraterrestrial conclusion far too quickly. "They seem to prefer the most bizarre explanation they could find," agrees Charles Cockell at the Open University, who studies the microbiology of extreme rocky environments.
What other explanations are there? Wainwright likens the red cells to spores from a rust fungus, or possibly pollen or algae. With Wickramasinghe and others, Wainwright has shown in balloon experiments that winds can carry microbes from the ground to high altitudes. Particles the size of those in the red rain could soar several kilometres above the Earth's surface. The dimpled shape could easily have arisen when the cells collapsed in the microscopy process. If that were true, he says, then the only mystery concerns the lack of DNA. "You wouldn't expect spores, microbes or algae not to have any DNA," he says. The simplest explanation is that Louis's experiments missed it, so Wainwright wants to repeat the tests. If the cells do turn out to contain DNA, then there is no great mystery. "I'd kind of relax if there was DNA there," says Wainwright.
If there is no DNA, Wainwright argues, the cells might be something extraordinary. He speculates, like Louis, that the lack of DNA might point to some kind of exotic life form, although he admits it would be paradoxical for cells without DNA to be classed as "living".
Cockell argues that there could be a simpler explanation - the red particles are actually blood. "They look like red blood cells to me," he says. The size fits just right; red blood cells are normally about 6 to 8 micrometres wide. They are naturally dimpled just like the red rain particles. What's more, mammalian red blood cells contain no DNA because they don't have a cell nucleus.
It's tough to explain, however, how 50 tonnes of mammal blood could have ended up in rain clouds. Cockell takes a wild guess that maybe a meteor explosion massacred a flock of bats, splattering their blood in all directions. India is home to around 100 species of bats, which sometimes fly to altitudes of 3 kilometres or more. "A giant flock of bats is actually a possibility - maybe a meteor airburst occurred during a bat migration," he says. "But one would have to wonder where the bat wings are."
Walker agrees that the particles in the red rain look uncannily like red blood cells. He says a simple test for haemoglobin could resolve this quickly. "If they believe they aren't red blood cells, then they need to explain how they've managed to eliminate that possibility," says Cockell. "I would have thought some more basic biochemical analysis of these cells would be worthwhile, and that should identify it, whatever it is."
"It's a pity that they don't realise this is interesting without all the extraterrestrial hype," Cockell adds. "How might you get blood into rain? I don't think anyone has observed an event where they've seen an animal ripped apart and its blood distributed in clouds. In some ways, that whole process is far more interesting than what Louis is trying to prove." For blood cells to survive would be astonishing: normally they would be destroyed within minutes if kept in rainwater, unless the salinity was the same as inside the blood cell.
In the next few weeks, the mystery of Kerala's red rain may finally be solved. Louis sent samples to Wickramasinghe's lab in Cardiff last month. As New Scientist went to press, he and Wainwright were still analysing them.
If they can't explain the origin of the samples, then the suggestion that they are alien life will gain credence. In that case, someone will have to verify an observation that Louis made which even he finds astonishing: that the cells replicate. In earlier unpublished papers, Louis says he cultured the red rain cells in unconventional nutrients, such as cedar wood oil, and showed that these DNA-devoid microbes divide happily at a temperature of 300 ?C. Louis admits he left these claims out of his latest paper because he thought they would be considered "too extraordinary".
Extraordinary is an understatement: if the cells really do replicate we'll have found the first evidence of extraterrestrial life. In the end, though, I didn't find any scientist willing to bet that the red rain of Kerala contained aliens. But everyone agreed it's a cracking good story that's crying out for a proper explanation. "I think you've got to be intrigued," said Wainwright. "If you're not intrigued, then what are you doing in science?"
From issue 2541 of New Scientist magazine, 02 March 2006, page 34
href="http://today.reuters.com/news/articlenews.aspx?type=scienceNews&storyid=2006-03-
06T204858Z_01_N06327000_RTRUKOC_0_US-SPACE-SUN.xml&rpc=22" target="_blank">Sun's next 11-year cycle could be 50 pct
stronger
By Deborah Zabarenko
Reuters
6 Mar 06
WASHINGTON (Reuters) - Sun-spawned cosmic storms that can play havoc with earthly power grids and orbiting satellites could be 50 percent stronger in the next 11-year solar cycle than in the last one, scientists said on Monday.
Using a new model that takes into account what happens under the sun's surface and data about previous solar cycles, astronomers offered a long-range forecast for solar activity that could start as soon as this year or as late as 2008.
They offered no specific predictions of solar storms, but they hope to formulate early warnings that will give power companies, satellite operators and others on and around Earth a few days to prepare.
"This prediction of an active solar cycle suggests we're potentially looking at more communications disruptions, more satellite failures, possible disruptions of electrical grids and blackouts, more dangerous conditions for astronauts," said Richard Behnke of the Upper Atmosphere Research Section at the National Science Foundation.
"Predicting and understanding space weather will soon be even more vital than ever before," Behnke said at a telephone news briefing.
The prediction, roughly analogous to the early prediction of a severe hurricane season on Earth, involves the number of sunspots on the solar surface, phenomena that have been monitored for more than a century.
TWISTED MAGNETIC FIELDS
Every 11 years or so, the sun goes through an active period, with lots of sunspots. This is important, since solar storms -- linked to twisted magnetic fields that can hurl out energetic particles -- tend to occur near sunspots.
The sun is in a relatively quiet period now, but is expected to get more active soon, scientists said. However, there is disagreement as to whether the active period will start within months -- late 2006 or early 2007 -- or years, with the first signs in late 2007 or early 2008.
Whenever it begins, the new forecasting method shows sunspot activity is likely to be 30 percent to 50 percent stronger than the last active period. The peak of the last cycle was in 2001, the researchers said, but the period of activity can span much of a decade.
The strongest solar cycle in recent memory occurred in the late 1950s, when there were few satellites aloft, no astronauts in orbit and less reliance on electrical power grids than there is now.
If a similarly active period occurred now, the impact would be hard to predict, according to Joseph Kunches of the National Oceanic & Atmospheric Administration's Space Environment Center in Colorado.
"It's pretty uncertain what would happen, which makes this work more relevant," Kunches said.
"What we have here is a prediction that the cycle is going to be very active, and what we need and what we're of course working on is to be able to predict individual storms with a couple days or hours in advance so the grids can take the action," Behnke said.
target="_blank">Meteorite falls in Northeast Brazil
Published in O ESTADO DE SAO PAULO
03.08.2006
In TABOACAL at SANTO ANTONIO DE JESUS rural area, PAULINA DE JESUS saw a huge fire ball crossing the sky. "After falling, the fire ascended about 30m into the sky" and burned a great forest area in the Atlantic Forest.
The meteorite left five holes in the land of about 2 meters in diameter.
The ANTARES Observatory, in the nearby the city of FEIRA DE SANTANA will conduct an investigation.
Translated from the Portugese by MA BN
Astronomer: "UFO" observed across Thailand is meteor
www.chinaview.cn
2006-03-13
BANGKOK, March 13 (Xinhuanet) -- The recent sighting of what appears to be an unidentified flying object (UFO) over Thai central province of Ayutthaya has left witnesses scratching their heads over what exactly it might have been while some astronomer and experts thought it was something like a meteor.
Morakot Areeya, head of a astronomy learning center, was quotedon Monday by the Bangkok Post as saying that he saw a burning object speeding across the sky at about 6:20 p.m. (1120 GMT) on March 4 in Ayutthaya's Nakhon Si Ayutthaya district. Some other witnesses also reported they have seen the unidentified object that night.
Worawit Thanwuttibandit, a cosmic adviser to the Thai Astronomical Society, said the object might have been a large meteor.
Dr Sarun Posayajinda, deputy director-general of the National Astronomical Research Institute, said it was possible that the object was some kind of space debris which had burst into flames on entering the earth's atmosphere.
Morakot took a photograph of the object, which he first thought was an airplane that had burst into flames. However, he was surprised to see the object continue to streak across the sky in an easterly direction before disappearing from sight.
Morakot said it did not appear that the object had struck the earth, rather it had traveled almost horizontally. He said some locals felt the object may have been some form of UFO.
"It is strange because after contacting a number of local amateur radio hams, none had learnt of any air crashes in the area," Morakot said
Mystery Booms Continue To Baffle Everyone
March 14, 2006
By Dan Tilkin
and KATU.com Web Staff
PORTLAND, Ore. - The source of those mysterious rumblings over the weekend that caught the attention of so many continues to be a mystery, although there is a focus on a potential answer.
The focus is on F-15s at the Portland Air Base, which KATU News was originally told were on the ground, but we later learned were not.
It turns out a group of F-15s were launched from the Portland International Airport Saturday night as part of three days of intensive training.
Within an hour of their departure, people started hearing things and feeling some rumblings. That is when the 911 calls began.
Even the commander of the F-15 squadron heard the strange noise from his home in Lake Oswego.
The logical explanation seemed to be that the fighter jets set off a sonic boom, but the Air National Guard says it does not make sense that so many people, from Longview to the Oregon coast, would hear the same sonic booms at the same time. A much smaller range of 10 to 20 miles is more likely.
With so many wondering what happened, the Air National Guard is continuing its investigation.
That leaves others to speculate about meteors and to do comparisons with a similar unexplained phenomenon in Florida last year and in Maine just last month.
Others speculate it is a secret government plane, code-named Aurora, which supposedly flies out of Area 51 in Nevada.
For years, unusually intense sonic booms rocked Los Angeles, with many believing it was Aurora passing by at four times the speed of sound.
Alien particles found in 'comet rain' put under microscope at Welsh university
Mar 20 2006
Tryst Williams, Western Mail
WELSH scientists have been spearheading the hunt for alien life that may have fallen to Earth in a shower of "red rain".
Astrobiologists will today continue to examine traces of matter that poured its blood-red deluge over the Indian state of Kerala for two whole months in 2001.
Chandra Wickramasinghe, of Cardiff University, is investigating claims made by one Indian researcher that the phenomenon may have been caused by a passing comet depositing extraterrestrial organisms over our planet.
Prof Wickramasinghe, head of the Cardiff Centre for Astrobiology, said, "I think this is potentially extremely important.
"My own personal interest is that for the past 30 years I have worked on the theory that life didn't start on Earth but on comets some 4,000 million years ago and there's an increasing body of evidence to support that point of view.
"We are intercepting cometary material and would expect microorganisms to come to Earth on a semi-regular basis."
The latest research started after red rain fell on the southwestern state of Kerala in August 2001.
Initial speculation suggested the rain's colour was the result of dust swept up by winds across Arabia.
But Godfrey Louis, a physicist at Mahatma Gandhi University in Kottayam, believes the particles that rained down contain types of cell-like organisms markedly different from anything else found on our planet.
Dr Louis said, "The red particles, which were part of the red rain, are possibly of extra-terrestrial origin.
"Under an optical microscope they appear like biological cells and the transmission electron microscopy shows a clear cell structure and their organic nature is indicated by the major presence of carbon and oxygen.
"But despite these biological indications the cells do not show the presence of any DNA.
"The genetic molecule DNA is present in all living organisms found on Earth. So the absence of DNA indicates that they are extraterrestrial."
There were several reports of a sonic boom in the region at the time the rains started, which may be consistent with meteors.
Nah. It couldn't have been a meteorite. Could it?
Mar, 23 2006
BURNABY/CKNW(AM980) - A loud explosion in Burnaby late last night has authorities scratching their heads.
About 11:05 the blast rattled windows and awakened neighbours near the Chaffey Burke Elementary School on Abbey Avenue.
Police responded with officers and a dog but came up empty handed. All they could find was a small hole in the ground.
No damage has been reported and there were no injuries.
Broken Comet On Its Way
By Tony Phillips
Science.NASA.gov
24 March 2006
In 1995, Comet 73P/Schwassmann-Wachmann 3 did something unexpected: it fell apart.
For no apparent reason, the comet's nucleus split into at least three "mini-comets" flying single file through space. Astronomers watched with interest, but the view was blurry even through large telescopes. The comet was a hundred and fifty million miles away.
We're about to get a much closer look. In May 2006 the fragments are going to fly past Earth closer than any comet has come in almost eighty years.
"This is a rare opportunity to watch a comet in its death throes-from very close range," says Don Yeomans, head of NASA's Near Earth Object Program at JPL.
There's no danger of a collision. "Goodness, no," says Yeomans. "The closest fragment will be about six million miles away--or twenty-five times farther than the Moon." That's close without actually being scary.
The flyby is a big deal. "The Hubble Space Telescope will be watching," says Yeomans. "Also, the giant Arecibo radar in Puerto Rico will 'ping' the fragments to determine their shape and spin."
Even backyard astronomers will be able to take pictures as the mini-comets file through the constellations Cygnus and Pegasus on May 12, 13 and 14.
Ironically, despite being so close, these comets will not be very bright. The largest fragments are expected to glow like 3rd or 4th magnitude stars, which are only dimly visible to the unaided eye.
"Remember," says Yeomans, "these are mini-comets."
They're not like the Great Comets Hayutake and Hale-Bopp of 1996 and 1997. Those could be seen with the naked eye from light-polluted cities. The fragments of 73P, on the other hand, are best viewed from the countryside-and don't forget your binoculars.
The number of fragments is constantly changing. When the breakup began in 1995 there were only three: A, B and C. Astronomers now count at least eight: big fragments B and C plus smaller fragments G, H, J, L, M and N.
"It looks as though some of the fragments are themselves forming their own sub-fragments," says Yeomans, which means the number could multiply further as 73P approaches. No knows how long the "string of pearls" will be when it finally arrives.
This is very uncertain; indeed, forecasters consider it unlikely. But an expanding cloud of dust from the 1995 break-up of the comet could brush past Earth in May 2006 producing a display of meteors.
"We believe the cloud is expanding too slowly to reach Earth only eleven years after the break-up," said astronomer Paul Wiegert at the University of Western Ontario. "but it all depends on what caused the comet to fly apart-and that we don't know.
"The most likely explanation is thermal stress, with the icy nucleus cracking like an ice cube dropped into hot soup: the comet broke apart as it approached the Sun after a long sojourn the frigid outer solar system," he explains. "If this is truly what happened, then the debris cloud should be expanding slowly, and there will be no strong meteor shower."
On the other hand, what if "the comet was shattered by a hit from a small interplanetary boulder?" A violent collision could produce faster-moving debris that would reach Earth in 2006.
Wiegert expects to see nothing, but he encourages sky watchers to be alert. It wouldn't be the first time a dying comet produced a meteor shower:
"One outstanding example is comet Biela, which was seen to split in 1846, and had completely broken apart by 1872," he says. "At least three very intense meteor showers (3000-15000 meteors per hour) were produced by this dying comet in 1872, 1885 and 1892."
Assuming a thermal breakup for 73P, Wiegert and colleagues have calculated the most likely trajectory of its dust cloud. Their results: dust should reach Earth in 2022, "producing a minor meteor shower--nothing spectacular. However," he adds, "the ongoing splitting of the comet means new meteoroids are being sent in new directions, so a future strong meteor shower from 73P remains a real possibility."
Fireball reported in skies over Kanto
The Yomiuri Shimbun
Mar. 31, 2006
Astronomical observatories have received a number of reports of a fireball, described as flashing orange or blue, seen in the skies over the Kanto region around 8:30 p.m. Wednesday.
Reports were received from Gunma, Ibaraki, Chiba and Shizuoka prefectures as well as Tokyo, and indicate that the unidentified object moved across the night sky from the west to the east.
"When dust from the cosmos falls to Earth, it emits a bright light in the air. It's likely that the figure was one such fireball that was especially large and bright," said a spokesman at the Gunma Astronomical Observatory in Takayamamura, Gunma Prefecture.
Scientists theorize comet killed off the mammoths
Jacob Berkowitz.
The age of mystery material found in southern Alberta, which could belong to an extraterrestrial object, coincides with the great ice age die-off
WASHINGTON, D.C. - It's widely accepted that a cosmic collision did in the dinosaurs. Now there's scientific suspicion that an extraterrestrial object, possibly a comet, is implicated in the demise of the large ice age mammals.
Stars to 'fall like rain' midnight of April 21
April 4th, 2006
"Chinese records say 'stars fell like rain' in the shower of 687 B.C. In recent times, however, the Lyrids have generally been weak," the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) said in its astronomical bulletin.
IT MAKES no difference who you are. Soon, opponents of President Gloria Macapagal-Arroyo who may have been wishing for nearly a year for certain things to happen can make all the wishes they want.
The auspicious hour is at midnight on April 21.
But to better appreciate the heavens, stargazers are advised to go somewhere dark, preferably some place without street lights-but safe.
Then look up.
A keen eye could see up to 20 "falling stars" per hour, courtesy of the annual Lyrids meteor shower that has not failed to provide a spectacle every year for the past 2,600 years.
"Chinese records say 'stars fell like rain' in the shower of 687 B.C. In recent times, however, the Lyrids have generally been weak," the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) said in its astronomical bulletin.
Up to 10 meteors can be seen every night this month, but the peak of the meteor shower, which lasts less than 24 hours, will be at midnight on April 21 to early morning of April 22.
"The observation of the meteors is most favorable after midnight when the constellation Lyra, the showers' radiant, is already more than 30 degrees above the northeastern horizon," PAGASA said.
Meteors are rock particles that burn due to friction and are pulled by the earth's gravitation, causing them to appear like stars falling from the sky.
Meteor showers occur every month except for three months of the year, said Bernardo M. Soriano Jr., chief of PAGASA's Atmospheric, Geophysical and Space Sciences branch.
The brightest and most spectacular shower is the Leonid meteor shower in November. This spectacle can hurl up to 100 meteors every hour.
"Now is the best time to watch the shower because generally the sky is clear. Even if there is La Ni?a, the absolute value of the rainfall is still smaller than the volume during the rainy season," he said.
Soriano said the best areas to watch a shower are dark places without streetlights. Artificial lighting causes light pollution, which diminishes the visibility of the sky, he said.
Those who are in well-lit places can use black cloth to cover their peripheral vision and make holes through which they could watch the sky, he added.
But is it in the stars, Brutus?
Or in ourselves?
Europe Sets Next Phase In Asteroid Deflection Project
AFP
Apr 05, 2006
Paris - The European Space Agency (ESA) said it had shortlisted three European consortia to submit proposals for its Don Quijote project, which seeks to deflect any future asteroid on a collision course with Earth.
The teams are respectively led by Alcatel Alenia Space, Qinetiq of Britain and EADS Astrium, each of which has long experience in European space projects, ESA said in a press release on Monday.
ESA, helped by an independent panel of experts, will assess their submissions in October, and the outcome will be made public in 2007.
The Don Quijote mission will comprise two spacecraft.
One of them, called Hidalgo, will smash into the asteroid at relatively high speed, while a second one, Sancho, will arrive earlier at the same asteroid to measure the variation on the asteroid's orbital parameters after the impact.
The risk of an asteroid collision with Earth is extremely remote.
But if such an event were to occur, and the rock were big, the immediate devastation could be continent-wide and there could be lasting changes to the planet's weather system.
The long reign of the dinosaurs is believed to have come to an abrupt end 65 million years ago when an asteroid or comet smashed into modern-day Mexico.
The collision kicked up so much dust that heat and light from the Sun were diminished, destroying much of Earth's vegetation and the larger species of land animals that depended on it.
Deflection is considered a safer bet than blowing up a dangerous asteroid with nuclear bombs. An explosion would break the asteroid into chunks, with the risk these pieces could hit Earth in turn.
Comment:
"The risk of an asteroid collision with Earth is extremely remote."If the risk is so remote, why all the running around and preparing for asteroid deflecting missions? Why bother?
Mystery boom rattles region
North County Times
2006/05/04
NORTH COUNTY - A mysterious booming sound rocked the region Tuesday morning, causing a flurry of phone calls to authorities who couldn't explain the cause.
"It sounded like someone was dropping a 500-pound bomb," said Sgt. J.T. Faulkner at the Poway Sheriff's Station.
Officials said there was no definite evidence to link the blast about 8:55 a.m. to atmospheric conditions, earthquakes, sonic booms or explosions from artillery training at Camp Pendleton.
"We really don't have anything to confirm the cause," said Stephen Rea, emergency services coordinator for San Diego County's Office of Emergency Services. "There was no damage throughout the county."
The U.S. Geological Survey didn't register anything in the immediate area.
"We felt something shake our building," said Lt. Jim Bolwerk at the sheriff's communication center in Kearny Mesa, where dispatchers immediately fielded phone calls from concerned residents.
Cpl. K.T. Tran, spokesman for Camp Pendleton north of Oceanside, said he didn't feel any shaking in his building. The base started training at 6 a.m. with 81mm mortars that can sometimes be heard up to 50 miles away.
"I felt it at my home, University City," said forecaster Philip Gonsalves of the National Weather Service. "All that happened was that my windows rattled. There's a lot of speculation (about the cause), but that's all it is."
Asteroid Crash on Mercury Splattered Earth, Study Says
Adrianne Appel
for National Geographic News
April 4, 2006
An asteroid collided with the still-forming Mercury some 4.5 billion years ago, sending chunks of the planet hurtling through space, scientists say.
What's more, the collision was big enough to send up to 16 million billion tons (16 quadrillion tons) of Mercury's rocky material tens of millions of miles to Earth, new computer simulations suggest.
Some scientists believe that Mercury was much larger as it was forming than it is today. It had a lighter, rockier outer layer, similar to that of Earth's, which was blasted away in the great crash, they say.
This would explain why Mercury is so different from its neighbors Venus and Earth. Mercury is very heavy for its size, due to an unusually large amount of iron, scientists believe.
All the planets are thought to have formed in much the same way, so how Mercury ended up being so different is not completely understood.
A team of scientists in Bern, Switzerland, decided to tackle the mystery. They ran a pair of extensive computer simulations to test the collision theory.
"You always try to prove an idea wrong. This work shows it could have happened in this way,'' said astronomer Jonti Horner, who will present his results tomorrow at a Royal Astronomical Society meeting in Leicester, England.
First, the scientists simulated the catastrophic collision of the young Mercury with a giant asteroid traveling at 16 miles (25 kilometers) a second.
The collision would have been so violent and energy-packed that it would have caused Mercury's outer layer to melt. Shock waves would have flung the material from the planet.
The rapidly escaping debris would have eventually cooled into particles 1 centimeter (0.4 inch) in diameter or smaller, Horner said.
At the end of this hours-long process, Mercury would have been left at 35 percent of its original size.
"You've lost more [of Mercury] than what is left,'' Horner said.
A second simulation followed Mercury's jettisoned particles through space. The bits, Horner says, would have traveled for millions of years.
"Mercury particles would've ended up on everything in the solar system," he said.
Some particles were swept up by Jupiter's gravity and flung from our solar system. Some landed on Earth.
Most would have gone to Venus. "It's the nearest stop,'' Horner said.
Exactly where they ended up was heavily influenced by where Mercury may have been at the time of the collision and exactly where the planet was hit, the simulations found.
The simulations determined that the particles wouldn't have fallen back to Mercury.
Because of the distance the particles would have been flung during the collision, it would have taken four million years for 50 percent of the particles to fall back to Mercury. By then, they would have already been carried away by solar radiation.
John Chambers, a research astronomer with the Carnegie Institution in Washington, D.C., agreed that Mercury bits may have landed on Earth.
"If Mercury was hit, especially by something big, pieces could have escaped and hit other planets,'' he said.
Hybrid comet-asteroid in mysterious break-up
09:30 11 April 2006
NewScientist.com news service
Jeff Hecht
Something substantial has broken off an icy 50-kilometre object beyond the orbit of Saturn, leaving puzzled astronomers trying to figure out why.
Comets have been seen breaking up before, but only after heating when passing close to the Sun or a gravitational disturbance following a close encounter with a planet.
However, at 1.9 billion kilometres, this object is very far from the Sun. Another mysterious feature is that much more gas and dust is escaping from the breakaway fragment than from the parent body. The disintegration has created a dust cloud more than 100,000 km across and which is several times brighter than the original object was before the event.
The object, called 60558 Echeclus, was discovered in 2000 and is a "centaur" - part rocky asteroid and part icy comet. Its new activity, revealed in images taken on 2 April, makes it look "really strange", says William Romanishen of the University of Oklahoma, US, one of the team that took the images. "The first thing that came to mind was a collision."
Earlier observations showed Echeclus rotates about once every 26 hours, so a fragment would need a push to escape its gravity, says Paul Weissman of the Jet Propulsion Laboratory, who spotted the original cloud of gas and dust around Echeclus on 30 December 2005.
Explosive sublimation
Such an impact on a comet-like body has not been observed before. But there are other possibilities, says Steve Tegler of Northern Arizona University, US, another team member. A likely one is that event was caused by explosive sublimation of volatile ices in Echeclus, resulting in material being blasted off, he says.
Tegler says the evaporating ice is probably carbon monoxide, with vaporises at about that distance from the Sun, where the object's temperature is about 80 degrees Kelvin, close to the sublimation temperature. No one has yet analysed the gas composition.
Another puzzle is the difference in activity between the main nucleus and the fragment. Freshly exposed ices normally sublimate, so "you'd expect equal activity from both pieces", Wiessman says. But the nucleus does not look very active.
Unstable orbits
Echeclus was discovered by the Spacewatch telescope in 2000, and at first looked like an asteroid. Then Weissman found it was surrounded by a coma, so astronomers also classed it as a periodic comet, 174P. The photos from 2 April show the coma has now spread out.
Echeclus belongs to a group of more than 100 centaurs with orbits well outside the main asteroid belt. Although originally from the distant Kuiper belt, they now orbit the Sun between Jupiter and Neptune, but will be ejected from those unstable orbits within tens of millions of years. Cometary clouds have bee reported around three other centaurs too.
Echeclus is currently moving towards the Sun on its 35-year orbit, and will pass closest to our star - about 880 million km - in April 2015. Other centaurs have become active as they moved inward, Tegler says. But none have shown such dramatic activity.
Daytime Meteor Spotted In Colorado
Vail Daily
07/06/2006
Steve Erickson and his boys have a pretty good view of the night sky. Tuesday, the daytime sky was pretty impressive, too.
As Erickson and his boys Colton, 11, and Cal, 9, were driving back to their home at Horse Mountain Ranch north of Wolcott Tuesday afternoon, they saw something - presumably a meteor - streak across the western sky.
"It was visible across probably a third of the sky, probably from Burns Hole to Muddy Pass," Steve said. "It looked like fireworks. When it separated, it had color to it."
The trail of smoke the meteor left then hung in the sky for several seconds after the thing had disintegrated.
"It was the biggest one I've ever seen," Colton said.
"It was better than seeing one at night," Cal said. "This didn't just streak across the sky and disappear." [...]
Comet breaking into 17 bits, fragments may be visible next month
UNI
12 April 06
Hyderabad - Comet 73 P Schwassmann-Wachmann, which is breaking up, is heading for a rendezvous with the earth next month coming closer than any other comet in the past 20 years.
"In 1995, it was seen to have broken into three bits, when it was about two hundred and forty million kilometers away from the earth. It now appears to have broken into nineteen fragments, the closest of these will be just nine kilometers away around May 12," Dr B G Sidharth, Director of the B M Birla Science Centre here, said.
However, these bits would not be very clear and be barely visible to the naked eye. The best time for viewing them would be between May 12 and 14, with the aid of binoculars or a small telescope," he said.
"At thist time, the fragments of the Comet will be in the constellations Cygnus (Hansa) and Pegasus (Khagashwa). All this astral phenomenon will be visible in the East from around midnight till the early hours of the morning in the West. There is a small chance that the sighting of the Comet will be accompanied by meteor showers due to its debris, but it seems unlikely," Dr Sidharth added.
The break-up of a comet is a common phenomenon and sometimes fragments may even crash into the earth, as happened in Tunguska (Siberia) in 1908, he said, adding that fortunately, the site of the impact was uninhabited. It is believed that this devastation was cuaused by the debris of the Comet Encke.
However, Dr Siddarth assured that there is no chance of frgaments from this particular comet hitting the Earth.
Hybrid comet-asteroid in mysterious break-up
Jeff Hecht
NewScientist.com news service
11 April 2006
Something substantial has broken off an icy 50-kilometre object beyond the orbit of Saturn, leaving puzzled astronomers trying to figure out why.
Comets have been seen breaking up before, but only after heating when passing close to the Sun or a gravitational disturbance following a close encounter with a planet.
However, at 1.9 billion kilometres, this object is very far from the Sun. Another mysterious feature is that much more gas and dust is escaping from the breakaway fragment than from the parent body. The disintegration has created a dust cloud more than 100,000 km across and which is several times brighter than the original object was before the event.
The object, called 60558 Echeclus, was discovered in 2000 and is a "centaur" - part rocky asteroid and part icy comet. Its new activity, revealed in images taken on 2 April, makes it look "really strange", says William Romanishen of the University of Oklahoma, US, one of the team that took the images. "The first thing that came to mind was a collision."
Earlier observations showed Echeclus rotates about once every 26 hours, so a fragment would need a push to escape its gravity, says Paul Weissman of the Jet Propulsion Laboratory, who spotted the original cloud of gas and dust around Echeclus on 30 December 2005.
Explosive sublimation
Such an impact on a comet-like body has not been observed before. But there are other possibilities, says Steve Tegler of Northern Arizona University, US, who works with Romanishen. He says it is most likely that the event was caused by explosive sublimation of volatile ices in Echeclus, resulting in material being blasted off.
Tegler says the evaporating ice is probably carbon monoxide, with vaporises at about that distance from the Sun, where the object's temperature is about 80 degrees Kelvin, close to the sublimation temperature. No one has yet analysed the gas composition.
Another puzzle is the difference in activity between the main nucleus and the fragment. Freshly exposed ices normally sublimate, so "you'd expect equal activity from both pieces", Wiessman says. But the nucleus does not look very active.
Unstable orbits
Echeclus was discovered by the Spacewatch telescope in 2000, and at first looked like an asteroid. Then Weissman found it was surrounded by a coma, so astronomers also classed it as a periodic comet, 174P. The photos from 2 April show the coma has now spread out.
Echeclus belongs to a group of more than 100 centaurs with orbits well outside the main asteroid belt. Although originally from the distant Kuiper belt, they now orbit the Sun between Jupiter and Neptune, but will be ejected from those unstable orbits within tens of millions of years. Cometary clouds have been reported around three other centaurs too.
Echeclus is currently moving towards the Sun on its 35-year orbit, and will pass closest to our star - about 880 million km - in April 2015. Other centaurs have become active as they moved inward, Tegler says. But none have shown such dramatic activity.
Clandestine comets found in main asteroid belt
Kimm Groshong
NewScientist.com news service
23 March 2006
You do not have to look to the outer edges of the solar system, or even out beyond Neptune to observe a reservoir of comets. A bevy of the ice-containing bodies lies disguised as main-belt asteroids between Mars and Jupiter, claim astronomers from the University of Hawaii, US.
David Jewitt and Henry Hsieh have dubbed the new population "main belt comets". They describe three objects with near circular, flat orbits in the asteroid belt that stream volatile materials, producing an observable tail for weeks and months at a time.
The finding backs a theory that ice-bearing asteroids - or "comets" - from this much closer region may have played an important role in forming the Earth's oceans.
Scientists once believed the icy comets from the outer regions of the solar system were the most likely source of the water that transformed the early Earth from a dry, barren world. But chemical analyses of comet water - carried out from a distance - ruled out the possibility.
Another possibility was asteroids. But it had seemed impossible to study the water content of asteroids since most of their water appears to have dissipated or is now buried too deeply to observe.
Window to the past
Now Jewitt says this new population within the asteroid belt may provide a way to sample the chemicals in water on or near the surface of these objects. And he says the main-belt comets hold promise for future study as components of the protoplanetary disc that surrounded the Sun - the disc from which the planets formed. "They're a window to some early epoch, back when objects were accreting," he says.
The new study underscores the increasingly hazy distinction between comets and asteroids. "There are different definitions of comet used by different people at different times," Jewitt told New Scientist.
The two traditionally recognised comet reservoirs are the Kuiper Belt, a frigid region beyond Neptune's orbit, and the even more distant Oort Cloud. One definition describes a comet as an object following a highly elliptical, often inclined orbit with origins in one of these two reservoirs.
Carbonaceous covering
But another definition involves what an observer sees either with the naked eye or through a telescope - a comet's streaming gassy tail as it loses ice and other volatile materials through being warmed by the Sun.
Jewitt says based on their nearly circular, stable orbits, the main belt comets are "completely asteroidal". You would never guess that they were anything but asteroids." But in terms of appearance, with their long-lasting tails, he says "they're definitely comets".
The team believes in order to survive at such proximity to the Sun, the volatiles in the main belt comets would have to be covered by a layer of possibly carbonaceous material. They say an impact event could then uncover some of the volatiles, allowing the Sun's heat to trigger the observed outgassing.
Activated asteroids
Asteroid expert Richard Binzel at MIT questions the need for the new classification. "I prefer to think of them as activated asteroids," he told New Scientist. "It's no surprise if some asteroids have some water content, particularly in the outer asteroid belt."
He says volatiles have been measured to make up about 10% of some carbonaceous meteorites that are thought to come from the region.
Jewitt says potentially tens of thousands of main belt objects contain ice and have simply not been observed during their active period. In order to be seen spewing dust, the objects would have to have been hit by a meteor size boulder within the last thousand years or so, he adds.
Journal reference: Science (DOI: 10.1126/science.1125150)
The comets' tale - Maybe the dirty snowball theory is wrong
By David L. Chandler
Globe Correspondent
April 10, 2006
Three fly-by missions since 2001 have confounded almost everything astronomers thought they knew about the makeup of comets.
Then, two weeks ago, University of Hawaii researchers announced the discovery of a whole new family of close-in comets -- which might help explain how the early Earth got its water.
Our lack of knowledge could have dire consequences, scientists warn, because -- unlike asteroids, whose paths can be predicted years in advance -- comets could strike Earth with little warning. The missions have proven that we don't know enough about these dazzling lumps of ice and dirt to know how to respond.
But now, one astronomer has come up with a theory that might tie some of the loose ends together.
Instead of the conventional view of a comet's nucleus as a solid, several-miles-wide rubble pile or dirty snowball, Michael Belton, a lead scientist for last year's Deep Impact comet mission, suggests that the nucleus may be more like a lump of papier mache -- built up from a random assortment of irregular sheets of varying thickness.
''The presence of layers is ubiquitous" in the nuclei seen so far, Belton said, ''and may be an essential element of their internal structure." In his view, the nuclei were built up gradually as hundreds of smaller bodies smashed together over time, each flattening out and sticking to the growing body, forming one layer after another.
Astronomers were startled and confused by the dramatic and unexpected differences between the nuclei of Tempel 1 (seen by last year's Deep Impact mission), Wild 2 (as seen by the Stardust mission in 2004) and Borrelly (seen by deep Space 1 in 2001).
Belton's new theory, which he outlined at a conference in Houston last month, identifies all the varied and unexplained features seen on these comets -- including supposed craters on Wild 2, mesa-like plateaus on Borrelly, and distinctly different, overlapping surface textures on Tempel 1 -- as different aspects of the layered model he nicknamed Talps (for ''splat" spelled backwards).
Clark Chapman, a specialist in asteroids and comets at the Southwest Research Institute in Boulder, Colo., agrees with Belton that ''it looks like comets have layers in them," but he said the theory is still untested. ''It's a first step toward trying to understand comets differently."
The new model would have significant implications for the life cycle of comets and for how we might attack a comet headed for Earth. Pushing aside a solid ball with a huge rocket or nuclear blast might make sense, but using the same approach against a ball of many layers might cause the comet to splinter and could magnify the damage rather than avert it, Belton suggests.
The find of a new type of comet -- the third known -- adds a lot of new questions to comet research and possibly helps answer a longstanding mystery: How the Earth has so much water when models suggest it shouldn't.
As the solar system's inner planets coalesced from the cloud of gas and dust swirling around the sun, the sun's heat caused water to evaporate. The new discovery suggests that Earth's water supply might have been replenished by some comets or asteroids that initially formed just a bit farther out and so might have retained their ice as they hurtled around the sun and eventually smashed into our planet.
Astronomers Henry Hsieh and David Jewitt of the University of Hawaii announced late last month that they have found comets with asteroid-like orbits -- circling the sun as planets do, between Mars and Jupiter, instead of the very elongated orbits characteristic of all previously known comets.
Finding comets like these suggests that there could be icy asteroids or comets that formed much closer to the sun than previously thought. They would have replenished Earth's water supply when they crashed into its surface.
''I think it's very significant," Jewitt said, to find such a fundamentally different group of comets, which must have formed separately from all the others.
But it will take more study to figure out how this new population will compare to the others and what kind of structure they might have. Being born in a hotter region of the growing solar system, for example, might have produced a different kind of layering, if any.
Belton, president of Belton Space Exploration Initiatives in Tucson, said he'd like to have a chance to prove his model by getting a closer look at some of these comets, particularly with a radar analysis -- which past missions couldn't perform -- that could clearly show whether the orb is layered deep down.
It may be a while before he gets that wish, but the European Space Agency's Rosetta mission will provide close-up views in 2014 of another comet nucleus and will use microwaves to probe its inner structure. Other comet missions have been proposed.
''The reconnaissance is over," Belton said. ''It's time to get into the detailed exploration phase."
- Copyright 2006 Globe Newspaper Company.
Ice crashes through college gym - No one is injured by the 2-foot chunk and no one knows yet where it came from.
By DARRELL R. SANTSCHI
The Press-Enterprise
April 13, 2006
A 2-foot-long chunk of ice that looked like compacted snow but whistled like an artillery shell crashed through the roof of the Drayson Center at Loma Linda University on Thursday morning.
No one was injured when the ice hit sometime between 8:55 and 9:15 a.m. The ice broke into pieces in the lattice work above the floor of the unoccupied Opsahl Gymnasium.
Maintenance workers retrieved a chunk about twice the size of a man's head, double-bagged it and stuck it in a freezer to save for Federal Aviation Administration officials.
Rolland Crawford, Loma Linda Fire Department division chief, said firefighters are not certain of the origin of the opaque white ice. University spokeswoman Julie Smith said a building repairman saw an airplane flying overhead at the time.
FAA spokesman Mike Fergus said investigators will review radar records to identify planes in the area at the time of impact. That will take at least a week, Fergus said. But the color of the ice may mean authorities will never determine where it came from, he said.
Blue ice comes from an aircraft's galley or lavatory. The source of ice of other colors can be mysterious, he said. Sometimes rime forms on the fuselage and breaks off, but that ice tends to be only 2 or 3 inches thick.
He said there have been cases in which ice fell and there were no aircraft in the vicinity. That could be naturally forming gigantic hail, Fergus said. He said the FAA follows up in such cases, but it gets a lower priority than investigations involving injuries or deaths.
Crawford said a ladder truck and three firefighters initially were dispatched to the campus. A supervisor followed and finally, both Crawford and Fire Chief Mike Norris.
"Chief Norris and I said, 'We've got to see this.' "
Crawford said the ice penetrated the sheet metal roof of the Drayson Center, went through a coating of tar paper and plywood underneath, then through a layer of insulation and the ceiling of the gymnasium. Pieces of ice lodged in the metal latticework just below the ceiling but apparently did not reach the gym floor.
"There were people outside the building who heard it," he said. "They said it sounded like an artillery shell going through the air. It was a whistling, whooshing sound."
Smith said no one was in the gym at the time.
A similar incident occurred in Fontana in August 2005, when a chunk crashed through the roof of a home in the 14000 block of Westward Drive.
Fragmented Comet Breaks Apart Even More
SPX
Apr 17, 2006
Boulder, CO - Astronomers tracking Comet 73P/Schwassmann-Wachmann 3 report that the near-Earth object continues to break apart, with at least 20 fragments now approaching the planet for a close encounter next month.
In the process of breaking up, pieces of the comet actually have grown brighter as they approach Earth and the sun. In particular, astronomers report, fragment B has brightened by a factor of 15 just since the beginning of this month. This phenomenon signals a possible breakup of 73P-B into even more fragments.
At present, fragment B is glowing like a 9th magnitude star, making it an easy target for backyard telescopes and CCD cameras. Fragment G also has split. Fresh ice exposed by the disruption is vaporizing, causing this fragment also to brighten nearly fifteen-fold since April 2, reaching a brightness of magnitude 12.
Amateur astronomers with backyard telescopes and CCD cameras can monitor the ongoing disintegration. Spaceweather.com is providing sky maps, images and more information on its Web site.
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